OK, so being a dumbass I bought a pyrometer without actually understanding what it does or how to read it. I blew my last ITR motor cuz it ran lean and popped. So not wanting that to happen to my new motor I wanted to monitor my AF from inside the car. Heard those AF gauges are just a light show - so - I bought myself a pyro gauge and put it in. Was told those are far more actuate. It's pretty. Has a pretty little red needle that moves side to side as the exhaust temps change. But for the life of me, I have no idea what my A/F is by looking at it. On the track it runs hot (12ish), on the street it runs cool (6ish) on the highway it run in the middle (8ish). I'm pretty sure the car is running rich from the black smoke and fuel smell, but how exactly can I tell on the gauge the car is running rich? Anyone have one on an NA setup? Thanks in advance.


Modified by RRRex at 12:01 AM 7/27/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RRRex &raquo;</TD></TR><TR><TD CLASS="quote">I'm pretty sure the car is running rich from the black smoke and fuel smell, ... but how exactly can I tell on the gauge the car is running rich?</TD></TR></TABLE>

You can't.
Should have gotten a reliable wideband A/F gauge.

Quick question though, where did you mount the Pyro (EGT) probe?
I ask this because it's said that cylinder #3 is usually the hottest on Honda motors.

 

Now I know.

It's mounted on the header in front of the Cat.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RRRex &raquo;</TD></TR><TR><TD CLASS="quote">Now I know.

It's mounted on the header in front of the Cat.</TD></TR></TABLE>

You should mount it 4" from the head to get nice consistent readings.

Up there, you ought to see 1300-1500 on the highway, 1600-1800 track. 600-800 idle. Something along those lines.

EGT is a general health gauge of the motor. It isn't isolated to just A/F. It also changes based on ignition timing, too. If you get preignition they will drop, if you retard the timing too much they'll go down. If you are running rich they'll be too cool, if you're running lean they'll be too hot.

It seems to be a gauge that, unless you're actually tuning a car with a wideband O2, doesn't tell you much by itself.

For reference, if you had a turbo, the temp drops about 200F (100C) when you move the EGT from before the turbo to after the turbo.


Edit:

Based on your EGTs, I'm 'guessing' you're rich but hard to tell since I don't have experience with that placement of the prope.